"We are all shocked and we're all asking each other 'Who lives there?'."

Mr Rana said he and his neighbours believed the house was empty and his attention was drawn to the window cleaner and neighbour because he thought they might be prospective buyers.

"As far as I knew, the last tenants had moved out of the house and the house was empty," he said.

"I was shocked that somebody was in there.

"It is sad. Everybody is shocked. I'm a father of four and my children are shocked as well."

Other neighbours said they believed the woman and the child had lived in the house for around three months.

A West Yorkshire Police spokesman said: " Police have launched a murder investigation following the death of a two-year-old girl in Bradford.

"The girl and a 36-year-old woman were found unconscious outside an address in Delamere Street at around 9.15am yesterday.

"Both were taken to hospital, but the child sadly died a short time later.

"The woman remains in hospital, where she is in a critical condition.

"A post-mortem was carried out last night, which revealed that the girl died of injuries consistent with a fall.

"A 36-year-old woman, who police can confirm is the child's mother, has been arrested on suspicion of murder."

Detective Chief Inspector Jon Morgan, added: " We are not looking for anyone else in connection with this incident, but are appealing for anyone with information to contact the police on 101 or Crimestoppers on 0800 555111."

This morning, flowers were laid outside the house, just off the busy Manchester Road in the city.